A microchip manufacturing process may deposit various material layers on a wafer and form a photosensitive film or photoresist on the deposited layers. The process may use lithography to transmit light through transmissive optics or reflect light from reflective optics to a reticle or patterned mask. Light from the reticle transfers a patterned image onto the photoresist. A process may remove portions of the photoresist which are exposed to light. A process may etch portions of the wafer which are not protected by the remaining photoresist to form transistor features.
The semiconductor industry continually reduces the size of the smallest transistor features to increase transistor density and to improve transistor performance. This desire has driven a reduction in the wavelength of light used in photolithographic techniques to define smaller transistor features in a photoresist.